Make the ann-benchmark AWS instance deletion resilient.

[jfrancoa]

It was noted that some of the AWS instances didn't cleanup properly, incurring in extra costs from our AWS EC2 account. This commit makes sure that the instance gets deleted and if for whatever reason it didn't after 5 minutes, the job will fail. So that the person monitoring the job can take a look at the AWS' instances or escalate the issue to SRE.

[orca-security-eu]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca

[jfrancoa]

CI run -> https://github.com/weaviate/weaviate-chaos-engineering/actions/runs/12117656779

[jfrancoa]

Now the job waits for the instance to be deleted:

Terminating instance i-00800f7df71c5b6a7
{
  "TerminatingInstances": [
    {
      "InstanceId": "i-00800f7df71c5b6a7",
      "CurrentState": {
        "Code": 32,
        "Name": "shutting-down"
      },
      "PreviousState": {
        "Code": 16,
        "Name": "running"
      }
    }
  ]
}
Waiting for instance to terminate...
Instance status: shutting-down
Instance status: shutting-down
Instance status: shutting-down
Instance status: shutting-down
Instance status: shutting-down
Instance status: shutting-down
Instance status: shutting-down
Instance successfully terminated
Deleting key pair key-ef97cc3b-65f5-4db2-bfa6-25b7e32df96c
{
  "Return": true,
  "KeyPairId": "key-0e0ab78ece2851ae2"
}
Deleting security group sg-0c39dc3db77059627